The main objective of this program is to contribute to an understanding of the molecular mechanisms responsible for cancer by investigating fundamental genetic processes involved in the control of cell growth and the maintenance of genomic stability. The projects that make up the Program collectively address a number of general issues relevant to this objective. These include the replication of tumor virus and cellular genomes, the mechanisms of malignant transformation by oncogenes, the control of the cell cycle, the mechanisms of DNA transposition and chromosomal rearrangement, the regulation of chromosome segregation, and the role of telomerase in normal growth and tumorigenesis.